Manzanillo (mänsänēˈyō) [key], city (1994 est. pop. 98,000), Granma prov., SE Cuba, a port on the Guacanayabo Gulf of the Caribbean Sea. A leading city on Cuba's southern coast, Manzanillo is a commercial center and the exportation point for the agricultural produce (sugarcane, rice, tobacco) of the Cauto plain. The city was founded in 1784 and was long a smuggling center involving British merchants from Jamaica. An attack by Great Britain on Manzanillo in 1792 destroyed numerous Spanish ships in the harbor and led to the fortification of the city.